"On February 28, 1997, NatWest Markets (NWM), the corporate and investment banking arm of one of the UK's largest banks, National Westminster, revealed that a 50 million loss had been discovered in its interest rate options and swaptions trading books. The loss figure escalated to 90.5 million after further investigations.

NWMs troubles started with a systematic mispricing of various options and swaptions by traders in its rate risk management group. As losses mounted, Kyriacos Papouis, who traded Deutschemark (DEM) interest rate options and swaptions, began to mismark options positions in the banks books in a concerted attempt to cover up the losses. "

" List of trading losses
The following contains a list of trading losses of the equivalent of USD100 million or higher. Due to the secretive nature of many hedge funds and fund managers, some notable losses may never be reported to the public. The list is ordered by the real amount lost, starting with the greatest. This list includes both fraudulent and non-fraudulent losses."

"A rogue trader is an authorised employee making unauthorised trades on behalf of their employer. It is most often applicable to financial trading, and as such is a term used to describe persons - professional traders - making unapproved financial transactions."

how bad does that suck to be the man whose bad decisions brought down a 200+ year old bank.

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They were in the book The Merchant Bankers. They had some history behind them for sure... I think they were complacent regarding oversight of Leeson, they were in London and he was in Singapore in his own office. They thought he could do no wrong...

when you are making that much, the risk managers are duplicating your trades, not 1 for 1, but duplicating just the same, that make s them oodles of dough, they secretly want u to win and will turn a blind eye, because it's profitable, u are their golden goose, . Don't think for a second these guys were trading overleveraged, unnoticed.